Heart valves regulate the movement of blood into and out of the chambers of the heart. The mitral valve, positioned between the left atrium and the left ventricle, can be subject to a condition known as mitral regurgitation, in which the mitral valve does not close properly and some backflow of blood occurs from the left ventricle back into the left atrium. For example, a mitral valve leaflet can experience prolapse during systole, thereby inhibiting leaflet coaptation and permitting backflow of blood into the left atrium.
Various procedures and devices have been proposed to address the condition of mitral regurgitation. For example, some mitral valve repair procedures involve removing a section of a valve leaflet in order to reduce its propensity for prolapse. Other procedures involve mitral valve replacement. The MITRACLIP (Abbott Vascular) is a device intended to be positioned across the mitral valve to create a double orifice, in an effort to allow the valve to close fully during systole.
US 2010/0331971 discloses cardiac valve downsizing devices and methods. The objective of these downsizing devices is to downsize the annulus of the valve by circumflexing all or substantially all of the chords. A downsizing device as disclosed in US 2010/0331971 is formed as a helix wherein a lower part of the helix is designed to extend on the ventricular side of the valve along an outer periphery adjacent the heart wall around the outermost chords. This outer periphery is accessed by extending the helix through a commissure at the periphery of the valve or through the annulus itself. Rotating the helix causes advancement of the helix so that part of the helix extends into the ventricle at the outer periphery around the outermost chords, while part of the helix is in the atrium, adjacent the annulus, thereby anchoring the device with respect to the atrium.
The Applicant's prior application US 2013/0006352 also relates to devices and methods for the repair of the functioning of heart valves. US 2013/0006352 discloses heart valve repair devices designed to draw the desired leaflet edge areas together. A device as disclosed in US 2013/0006352 comprises a first section having a generally spiral shape, with the spiral shape emanating from a center of the spiral, and a second section connected to the first section at the center of the first section. The first section is positioned on the ventricular side of the heart valve, with the selected chords positioned within the path of the generally spiral shape, and the second section is positioned on the atrial side of the heart valve. US 2013/0006352 discloses that, in a device as described therein, the ventricular section draws the captured chords together, thereby pulling the desired valve leaflet areas together, while the atrial section stabilizes or anchors the device relative to the atrium.
There is a continuing need for improved treatment for mitral valve regurgitation and for the repair of the functioning of heart valves in general. The various procedures and devices previously proposed can be improved upon in terms of their overall clinical outcome, ease of use, reduction of procedure time and risk, and/or reduction of cost.